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United States Patent | 6,177,279 |
Sun ,   et al. | January 23, 2001 |
A process for extracting inorganic ionic contaminants from a front surface of a silicon wafer for chemical analysis. The wafer is placed in a container upon a support which holds the wafer in a generally level orientation and isolates the wafer to inhibit air circulation over the front surface. Air circulation can introduce contaminants to the extraction fluid, causing a false measurement of contaminants on the wafer. A layer of extraction fluid is deposited upon only the front surface of the wafer and held for a period of time so that contaminants on the front surface are extracted into the layer of fluid. A portion of the layer of fluid is collected by a sampling device for subsequent analysis.
Inventors: | Sun; Peng (O'Fallon, MO); Adams; Marty (St. Charles, MO) |
Assignee: | MEMC Electronic Materials, Inc. (St. Peters, MO) |
Appl. No.: | 191715 |
Filed: | November 12, 1998 |
Current U.S. Class: | 436/175; 73/863.21; 73/863.83; 73/863.84; 134/2; 134/3; 134/21; 134/26; 134/32; 134/34; 134/36; 436/73; 436/100; 436/101; 436/102; 436/103; 436/106; 436/110; 436/119; 436/124; 436/125 |
Intern'l Class: | G01N 001/00 |
Field of Search: | 134/3,21,2,26,32,34,36 73/863.21,863.84,863.83 436/73,100,101-103,106,110,119,124,125,175 |
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Foreign Patent Documents | |||
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